BACKGROUND: During 1997-99, the INTERMAP Study - with NHLBI support - surveyed 4,680 men and women ages 40-59 from 17 diverse population samples in Japan (4 samples), the Peoples Republic of China (PRC) (3 samples), the UK (2 samples), and the USA (8 samples). With standardized, quality-controlled methods, 4 24-hour dietary recalls, 2 timed 24-hour urine collections, 8 blood pressure (BP) measurements, anthropometric, and questionnaire data (on sociodemographic and biomedical traits) were accrued for all participants. Foods, beverages, and supplements were converted to nutrients (83 total) with use of up-dated, enhanced, standardized tables on nutrient composition (4 tables, 1/country). Urines were analyzed for Na, K, Ca, Mg, creatinine, albuminuria, amino acids. A high-quality central laboratory in London, England completed nuclear magnetic resonance (NMR) spectroscopic analyses of all urine specimens (2 from each of the 4, 680 participants plus 10% randomly selected, blinded split specimens for external quality control). All data underwent extensive quality control checks and were computerized and secured at the two INTERMAP International Coordinating Centers in Chicago and London, England. AIMS: Overall aim is - in a highly cost effective way - to add a new dimension of research information and thereby achieve a qualitative advance in knowledge on the etiopathogenesis of population-wide adverse BP levels (prehypertensive and hypertensive), i.e., develop a new epidemiologic area based on the urinary metabolic products whereby multiple dietary and diet-related factors influence BP. Based on the vast, unique array of high quality BP, nutritional, urinary metabolite, etc. data available and accruable, the specific aims are to identify and quantify - from NMR spectra in hand plus mass spectrometry and other techniques - urinary metabolites discriminatively related to BP and to each of several dietary (vegetable protein, soy protein, arachidonic acid, Na/K), diet-related sociodemographic (education, ethnicity) and anthropometric (body mass index) factors impacting BP. Advanced bioinformatics techniques and biochemical methods are to be used to address each aim. SIGNIFICANCE: The BP problem is population-wide;waiting for individuals to develop hypertension and then treating them with drugs is an inadequate strategy. This study - by identifying specific urinary metabolites implicated in the etiologic pathways whereby adverse dietary/lifestyle patterns lead to population-wide adverse BP levels - can help create fully effective strategies for prevention/eradication of the mass BP problem.